Internal combustion engine control



Sept.'26, 1944. H. ALEXANDERSON ,3

' INTERNAL COMBUSTION ENGINE CONTRQL I Filed Nov. 4, 1941 3 Sheets-Sheet l DRAIN HULES INDEXING VIEW OF BF INNER LINER DOES NOT INDEXNG SLOTS AFFECT DILHDLE LUNNECTUNS TD SERVE] Mun-ma. gwuem/fm Han aid fllsxandersolz.

P 1944- H. ALEXANDERSON INTERNAL COMBUSTION ENGINE CONTROL 3 Sheets-Sheet 2 Filed Nov. 4, 1941 Sept. 26, 1944.

H. ALEXANDERSON INTERNAL COMBUSTION ENGINE CONTROL Filed Nov. 4, 1941 64 .aa as 3 Sheets-Sheet 5 66 L 'MUMMH & 76 f I DRAIN SUPPLY 1: 'l Z012 DRAIN Fatented gent. 26, 1944 UNITED STATES AsNT OFFIE 2,358,345 INTERNAL COMBUSTION ENGINE CONTROIL Howard Alexanderson, Wood-Ridge, N. J., as-

signor to Bendix Aviation Corporation, South This invention relates to internal combustion engine operation, and particularly to the control of the position of the throttle governing the supply of combustible mixture-to the combustion chambers of the engine.

The object of the invention is to provide improvements in the type of throttle regulator disclosed in Patent No, 2,205,354 to David Gregg et al.

This and other objects of the invention will become apparent from inspection of the following specification when read with reference to the accompanying drawings wherein is illustrated the preferred embodiment of the invention. It is to be expressly understood, however, that the drawings are for the purpose of illustration only, and are not designed as a definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawings, wherein like reference numerals refer to like parts throughout the several views,

Fig. 1 is a view in elevation of a device embodying the invention;

Figs. 2, 3 and 4 are sectional views of the valve assembly along the lines 22, 3-4 and 4-5, respectively, of Fig. 5;

Fig. 5 is a longitudinal sectional view along the line 5-5 of Fig. '7;

Fi 6 is a. transverse sectional view along the line 6-6 of Fig. 5;

Fig. '7 is a view partly in elevation and partly in section along the line l-l of Fig. 5;

Fig. 8 is a transverse view along the line 8--% of Fig. 5; and

Fig. 9 is a diagram of the fluid connections between the valve assembl and the servo unit.

Referring first to Figs. 1 and 5, reference characters ll and I2 designate levers having operative connection with shafts It and I4, respectively; the lever ll being adapted for manual operation in the manner of the linkage ll, l2 of the Gregg et a1. patent above referred to, and the lever l2 having operative connection with the throttle, not shown, and therefore corresponding to the member it of the said Gregg et a1. patent. The shaft It (and therefore the lever I2) is adapted to be swung in both directions to produce a corresponding shifting of the throttle in response to manual shifting of the lever l l, and also in response to automatic shifting of a servo element it having a hub portion ll (Figs. 5 and 8) internally splined or serrated to engage corresponding splines or serrations l8 on the'central portion of the shaft is. The servo element It is shown in Fig. 8 as in the form of a rockable piston, 0r vane, movable between two radial abutments 2! and 22 in response to the admission and exhaust of fluid pressure to and from the sector shaped chambers 23 and 24 which are formed by the abutments 2i and 22 on the one hand, and the vanes IS on the other; the outer portion 2'! of the vane being adapted to fit snugly upon the inner cylindrical surface of the housing member 2-8 for fluid tight engagement therewith.

The means for controlling the alternate supply to, and exhaust from, the chambers 23 and 24 is shown as including a valve assembly consisting of a central movable plunger portion 3| (see Fig. 5) an inner valve sleeve 32 and an outer valve sleeve 33; the inner sleeve 32 being rotatable in respect to the other for proper indexing of the ports therein, after: which the unit is fixed in the adjusted position by pin 34, cap 36 and the final securing element 31. The valve assembly is housed in the central portion 38 which extends upwardly from the main housing 39 of the device, and is located directly above the linkage 4! connecting the manually operable shaft l3 with the inner reduced end portion 42 of the driven shaft H. A second linkage 43 (see Figs. 5 and 6) connects with the linkage 4| as indicated at 44 in Fig. 6. connecting with the linkage 4| is a third linkage 46 whose lower end link is operatively connected to a rockshaft 49 journaled in a-bearing 5| carried by the housing 39 and adapted to receive the lower aperturedend portion 52 of a lever 53 which is best shown in Fig. 7. An inner reduced end pin portion of shaft i8 is positioned in eccentric relation to the axis of rotation of the shaft Ill. The link 66 is pivotally mounted on the inner pin portion of shaft I8 so that the link 44 will swing in response to rotation of shaft l8--I4; but the pin and link 44 are not rigidly fastened, one to the other, as the link 54 can also be swung by movement of the link 41, even though the shaft i8-l4 and inner pin portion of shaft i8 are held stationary by the balanced pressures acting upon opposite sides of vane IS. The same is true of the connection between the shaft l3 and the horizontal link extending from link it to link ll. The shaft l3 has likewise provided an inner end pin portion positioned in eccentric relation to the axis of rotation of the shaft l3, on which eccentrio pin portion the horizontal link extending from link M to link 48 is pivotall mounted. Thus, movement may be imparted to the horizontal link connecting links M and 46 by movement of the inner eccentric pin portion of shaft l3 and also by independent movement of the links 4| and 46.

The lever 53 has operative pivotal connection with the outer end of a reoiprocable element 58 constituting part of the novel diaphragm assembly whose flexible element is shown at 51. The diaphragm assembly also includes a centrally bored and threaded plate 58 with which the corresponding threads 59 of the member 58 have operative engagement. A nut BI is also threadedly engaged with the member 58 and serves to clamp the flexible diaphragm 51 to the member 58 at the central portion of the diaphragm. At taching to the plate 58 at its periphery is a flexible corrugated sheet 63 whose opposite end attaches to the periphery of a plate 64 which is secured to the end surface 68 of the housing 39 as indicated at 61 and 68. The member 63 thus constitutes a bellows adapted to be pre-evacuated, and a coiled compression spring H is mounted in the bellows to urge the plate 58 (and hence the diaphragm 81) in a rightward direction as viewed in Fig. 7, thereby opposing the collapsing tendency of the evacuated bellows, and holding the latter in equilibrium.

Fluid under pressure is supplied by means of an oil pump (not shown) operated by the engine whose throttle is to be controlled; and from the said pump the oil under pressure is adapted to be supplied to the chambers 23 and 24 of the servo unit under the control of the movable plunger 3| of the valve assembly, which plunger is in turn under the control of the linkage 53, 52, 48, 48, 4| and 43 in the central chamber iii; the said linkage being urged in one direction by the pressure of the spring H upon the elements In and B1, and in the opposite direction bythe pressure of the air that is supplied to the chamber 14 by way of the conduit shown at 8| in Fig. 5, which conduit has connection at its opposite-end, (not shown, but see connection 38 in the Gregg et al. patent above referred to) with the intake manifold of the engine whose combustible mixture supply is to be regulated.

A novel feature is the provision of oil or other liquid filling the space between the elements 84 and 58, on the one hand, and the inner surface of the slack diaphragm 51 on the other. This oil constitutes a damping agency as well as constituting the means for transmitting to the bellows 63 the pressure being applied to the diaphragm 51 by the air entering the chamber II from the intake manifold by way of conduit 8i. In other words, the pressure which opposes the spring H (and therefore, in conjunction with said spring constitutes the operating means for the valve shifting linkage 56, 53, etc.) is transmitted by the slack diaphragm 51 directly to the oil inthe space 95, and from said oil the pressure is transmitted to the bellows 63. Hence the slack diaphragm 51 is not loaded in any way whatever, and serves merely to retain the oil in the space 88. Thus there is provided a, novel method of damping the vibrating tendency (which is characteristic of a bellows of the type indicated at 63) which novel method at the same time serves to segregate the damping'liquid from the supply of air which is introduced to the chamber II by way of the conduit 8 I.

Fig. 9 shows diagrammatically the manner in which the shifting of the plunger ll of the valve assembly operates to supply fluid to one side or the other of the servo-motor l8 of Fig. 8, while at the same time permitting an exhaust of operating fluid from the opposite side thereof the conduits connecting the valve chamber with the two chambers 23, 24 of the servo unit being indicated currently prevailing.

at I! and II in Fig. 9, and the supply conduit at ll, while the two exhaust ("drain") passages are indicated at iili and H12, the former being the exhaust passage when chamber 24 is being evacuated by way of conduit 98. and the passage I02 being the exhaust passage when the chamber 23 is being evacuated by way of conduit 91.

The word indexing" as used herein means the-turning of one of the valve sleeves with respect to the other, to bring about the desired radial alignment of the ports of one with those of the other. Once this indexing" has been accomplished, there is no further relative rotation between these valve sleeves. That is, the alternate opening and closing of the several ports is accomplished, during operation of the device. by the rectilinear motion of-the valve plunger 3 I, and not by any relative movement of elements 32 and 88.

In operation, the valve plunger will remain in the neutral position so long as the carburetor throttle setting is correct for maintenance of the desired pressure in the intake manifold of the engine, at the engine loading and altitude con- When engine loading or altitude changes, however, the intake manifold pressure will change correspondingly. If the manifold pressure increases the pressure in chamber 15 will increase correspondingly, as the chamber I! is connected to the intake manifold by the conduit 8|. displacement of the slack diaphragm 67, and the pressure thus exerted upon the interposed liquid II will cause a contraction of the bellows 83-the liquid itself being incompressible, of course. The resulting contraction of the bellows 88 (axially) will cause members 58, ,66 to shift to the left. and this will cause arm 53 to turn about the pivot Ii. This turning will move the linkage 48, 4|, 44, 43 and hence the valve plunger 3| will be shifted to a lower position. This shift of the valve being from servo-motor chamber 24 to the outlet I 0i (Fig. 9) and the other path being from pressure source 88 to the servo-motor chamber 23. The pressure thus exerted on vane it of the servomotor will cause rotation of shaft l8i4 and a corresponding change in throttle setting, to restore intake manifold pressure to the predetermined point. During this rotation of shaft IBI4 the link 44 will swing with the shaft (due to the eccentricity of,the inner pin portion of thcshait IS in relation to the axis of rotation of the shaft i8) and this swinging of the link 44 will restore valve plunger 3i toward the neutral position. Thus equilibriumis restored by the follow-up" action of shaft i8-i 4 on link 44.

When ma'nifold pressure drops below the predetermined point, the bellows 88 will expand to shift member 68 to the right. and the linkage will then cause valve plunger 3! to move to a higher position. Again two parallel paths of flow will be established, but this time they will operate to swing vane IS in the other direction, thus shifting the throttle link it oppositely to the direction heretofore referred to. The follow-up" action will again restore the valve to neutral when manifold pressure has been restored to normal.

Likewise upon manual adjustment of the lever ii there will be imparted a movement to the eccentric inner pin portion of the shaft i3, which as previously explained will cause the link horizontally connecting the links 48 and 4| to swing in such a manner as to pivot on its connection to the link 48 so as to move the linkages 4|, 44, 48

This pressure increase will cause plunger .will establish two parallel paths of flow; one path and hence the valve plunger 3| in a direction to aflect an adjustment of the throttle setting. The latter movement will also affect an adjustment of the value of the normal manifold pressure setting at which the bellows 51 will adjust the valve plunger 3| to a neutral position by varying the position of the eccentric inner pin portion of the shafts l3 and 18. The follow-up action previously described will again restore the valve plunger 3| to a neutral position upon the maniiold pressure attaining the adjusted normal value determined by the adjustment of the lever I I.

What is claimed is:

1. Motion transmitting means comprising a slack diaphragm, a bellows having an end plate to which the central portion of said slack diaphragm is mechanically clamped, so that the said central portion of said slack diaphragm is at all times caused to follow along with the movement of said bellows, and a casing closed at one end by said slack diaphragm, said casing containing said bellows, and also containing a quantity or liquid completely filling the space between said bellows and said slack diaphragm, whereby pressure variations acting upon one side of said slack diaphragm cause movement of the liquid on the opposite side thereof and thus produce a corresponding movement of said bellows.

2. Motion transmitting means comprising a slack diaphragm, a bellows, a casing closed at one end by said slack diaphragm, said casing containing said bellows, and also containing a quantity of liquid completely filling the space between said bellows and said slack diaphragm, whereby pressure variations acting upon one side of said slack diaphragm cause movement of the liquid on the opposite side thereof and thus produce a corresponding movement of said bellows, and means for mechanically clamping the central portion of said slack diaphragm to said bellows, so that the said central portion of said slack diaphragm is at all times caused to follow along with the movement of said bellows.

HOWARD ALEXANDERSON. 

